Maprotiline Hydrochloride
(ma proe' ti leen hye'' droe klor' ide).
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C20H23N·HCl 313.86

9,10-Ethanoanthracene-9(10H)-propanamine, N-methyl-, hydrochloride.
N-Methyl-9,10-ethanoanthracene-9(10H)-propylamine hydrochloride [10347-81-6].
» Maprotiline Hydrochloride contains not less than 99.0 percent and not more than 101.0 percent of the labeled amount of C20H23N·HCl, calculated on the dried basis.
Packaging and storage— Preserve in tight containers.
USP Reference standards 11
USP Maprotiline Hydrochloride RS Click to View Structure
B: Ultraviolet Absorption 197U
Solution: 100 µg per mL.
Medium: methanol.
Absorptivities at 266 nm and 272 nm, calculated on the dried basis, do not differ by more than 3.0%.
C: A solution (1 in 200) responds to the tests for Chloride 191, when tested as specified for alkaloidal hydrochlorides.
Loss on drying 731 Dry it in vacuum at 80 to constant weight: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.1%.
Chromatographic purity—
Standard solutions— Dissolve USP Maprotiline Hydrochloride RS in methanol, and mix to obtain a stock standard solution having a known concentration of 20 mg per mL. Dilute quantitatively with methanol to obtain Standard solution having a known concentration of 0.10 mg per mL. Dilute quantitatively with methanol to obtain Standard solutions, designated below by letter, having the following compositions:
Dilution Concentration
(µg RS
per mL)
Percentage (%,
for comparison
with test
A (undiluted) 100 0.5
B (4 in 5) 80 0.4
C (3 in 5) 60 0.3
D (2 in 5) 40 0.2
E (1 in 5) 20 0.1
Test solution— Dissolve an accurately weighed quantity of Maprotiline Hydrochloride in methanol to obtain a solution containing 20 mg per mL.
Procedure— In a suitable chromatographic chamber (see Chromatography 621), place a volume of a solvent system consisting of a mixture of secondary butyl alcohol, ethyl acetate, and 2 N ammonium hydroxide (6:3:1) sufficient to develop a chromatogram. Place a beaker containing 25 mL of ammonium hydroxide in the bottom of the chamber, and allow it to equilibrate for 1 hour. Apply 5-µL portions of the Test solution, the stock standard solution, and each of the Standard solutions to a suitable thin-layer chromatographic plate coated with a 0.25-mm layer of chromatographic silica gel that has been pre-washed with chloroform by allowing chloroform to move the full length of the plate, and dried at 100 for 30 minutes, and allow the spots to dry. Develop the chromatograms until the solvent front has moved about three-fourths of the length of the plate, remove the plate from the developing chamber, mark the solvent front, and allow the solvent to evaporate. Expose the plate to hydrogen chloride vapor for 30 minutes, expose it to a high-intensity UV light irradiator (1000 to 1600 watts) [Caution—UV irradiators emit UV radiation that is harmful to eyes and skin. ] until the spot in the chromatogram of Standard solution E is clearly visible, and compare the chromatograms under long-wavelength UV light: the RF value of the principal spot obtained from the Test solution corresponds to that obtained from the stock standard solution; and the sum of the intensities of all secondary spots obtained from the Test solution, compared with those of the principal spots obtained from the Standard solutions, corresponds to not more than 1.0%.
Assay— Dissolve about 600 mg of Maprotiline Hydrochloride, accurately weighed, in 25 mL of mercuric acetate TS, and titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically, using a glass electrode and a calomel electrode containing saturated lithium chloride in glacial acetic acid (see Titrimetry 541). Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 31.39 mg of C20H23N·HCl.
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Monograph Hariram Ramanathan, M.S.
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